|
Stock-Based Compensation (Tables)
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12 Months Ended |
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Dec. 31, 2012
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
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| Employee stock-based compensation expense |
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Year ended December 31, |
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2012 |
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2011 |
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|
2010 |
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|
Employee stock-based compensation expense
|
|
$ |
4,342 |
|
|
$ |
3,062 |
|
|
$ |
1,731 |
|
|
Tax effect on employee stock-based compensation expense
|
|
|
(1,643 |
) |
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|
(1,159 |
) |
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|
(655 |
) |
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Net effect on income
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|
$ |
2,699 |
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|
$ |
1,903 |
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$ |
1,076 |
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| Weighted average assumptions used to value options granted |
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Year ended December 31, |
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2012 |
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2011 |
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2010 |
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Grant date fair value of options
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|
$ |
4.96 |
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|
$ |
5.14 |
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|
$ |
3.71 |
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Volatility
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|
39.7% |
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|
39.4% |
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|
37.5% |
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Risk-free interest rate
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1.2% |
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2.37% |
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2.2% |
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Dividend yield
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0.0% |
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0.0% |
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0.0% |
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Expected term (in years)
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6.0 |
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|
6.0 |
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6.2 |
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| Summary of option activity |
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Shares |
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Weighted-
Average
Exercise Price |
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Weighted-Average
Remaining
Contractual Life
(Years) |
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Aggregate
Intrinsic Value |
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Outstanding as of December 31, 2009
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3,285,579 |
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|
$ |
6.70 |
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Granted
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2,049,461 |
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|
9.18 |
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Exercised
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(296,188 |
) |
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|
6.50 |
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Forfeited
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(40,515 |
) |
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|
7.81 |
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Outstanding as of December 31, 2010
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4,998,337 |
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|
7.64 |
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7.5 |
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$ |
47,083 |
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Granted
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|
486,833 |
|
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|
12.37 |
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Exercised
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(447,528 |
) |
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6.14 |
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Forfeited
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(173,924 |
) |
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|
9.36 |
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Outstanding as of December 31, 2011
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4,863,718 |
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|
8.19 |
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6.8 |
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18,704 |
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Granted
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738,915 |
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|
12.53 |
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Exercised
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(298,947 |
) |
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6.92 |
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Forfeited
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(26,274 |
) |
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|
11.03 |
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Outstanding as of December 31, 2012
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5,277,412 |
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|
8.86 |
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6.3 |
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26,885 |
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Options exercisable
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3,378,591 |
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7.70 |
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5.2 |
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21,124 |
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| Schedule of Exercise prices of stock options outstanding |
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Year ended December 31, |
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2012 |
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2011 |
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2010 |
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Total intrinsic value of options exercised
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|
$ |
1,611 |
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$ |
3,082 |
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$ |
1,511 |
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Cash received from exercises of stock options
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|
2,069 |
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2,747 |
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1,925 |
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Cash received from issuance of restricted stock
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2,759 |
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- |
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- |
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| Summary of prices whereby company granted employee stock options |
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Grant Date
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Options Granted |
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Fair Market Value
of Common Stock
(per share) |
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February 22, 2010
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|
71,000 |
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|
$ |
13.45 |
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Restricted Stock [Member]
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|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
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| Summary of unvested stock awards activity |
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Number of
Shares |
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Weighted-
Average Grant
Date Fair Value
per Share |
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Balance at December 31, 2010
|
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- |
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$ |
- |
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|
Granted
|
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77,224 |
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|
12.38 |
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Vested
|
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|
- |
|
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|
- |
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Forfeited
|
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(3,404 |
) |
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|
12.55 |
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Balance at December 31, 2011
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73,820 |
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|
12.37 |
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Granted
|
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|
714,934 |
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|
12.50 |
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Vested
|
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(24,568 |
) |
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|
- |
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Expired/cancelled
|
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(1,064 |
) |
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|
12.45 |
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Forfeited
|
|
|
(4,132 |
) |
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|
12.49 |
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Balance at December 31, 2012
|
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|
758,990 |
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|
12.49 |
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